Sizing of fibrous materials and compositions useful for sizing and for other purposes



Patented Jan. 5, 1954 Iheodoreli. Bradley, Oakland, -Galif., assignor tohell Development Company, San Francisco, Calif., a corporation ofDelaware N 9 Drawing. Application June l5, 1 95l,

Serial No. 33321 1 This -invent ion relates to the sizing of paper,cardboard, textile threads or fabrics, imitation leather and relatedfibrous materials. It deals with improved methods pf sizing suchmaterials whereby they may be rendered more resistant to water thanheretoforeand with new compositions which are not onlvvaluable sizingagents but also have other useful applications.

4 A widevariety of materials have been used for i e fibers 9 t fo e ointYP Thse i clude, for example, resins of various kinds, both natural andsynthetic, paraffin, waxes of difierent -types, bituininous or asphalticmaterials, tars, etc., but the most widely used sizing material employedin general commercial practice is rosin or colophony; The usualprocedure in paper sizing, for instance, is to add an aqueous dispersionof the sizing agent to the fibers to'be sized :in-the beater or Hollandmachinewhere the .size is precipitated on the fibers with paper makersalum 'or the like. This is a-very convenient method of sizing :but,particularly in recent years, hasbecomerelaatively expensive due to theincreased cost of :rosin. Itfurthermore doesnot provide the :mostdesirable sizing, especially where a highly waterproof product .isrequired, as, for example, kraft wrapping paper, cardboard and the like.

An important object of the present invention is to provide alsizingagent which overcomes the ,foregoing disadvantages of conventionalsizeszand which will be more economical .to manufacture -and use.Another important .obj ect .is to provide :a paper sizing compositionwhichrmay be derived entirely from petroleum. A further object is toprovide improved articles of manufacture, :parzticularlysized paperandthe like, which are-more water-resistant than :prior products .of asimilar :type. Still another object is to provide new emulsifiablecompositions which are useful not only as sizing agents but also haveother imp a -M srs i l be m fully p ted e hereinafter. =Still otherobjects and advantages ofthe invention will be apparent-fromthefollowing description of the invention in some of its morepreferred forms, it being understood that h io :isimi ih r i bi ihroadly a lica l asr eviously pointed o t.

' "Ithas bemfoundthat especiallyadvan ase- 10 Claims. (0].. 22- 3;)

2 pus composition for sizing paper and related fibrous materialscomprises a novel mixture of salts of naphthenic acids having acidnumbers less than 200 with conventional sizing agents, or preferablywith the predominantly cyclic extracts obtainable from mineral oils. Forpurposes of convenience, the naphthenic acids and naphthenic acid'saltsused will be referred to generically hereinafter as naphthenat'es'. Theacid numbers of the naphthenic acids as used herein refer to the numberof milligrams of potassium hydroxide which will neutralize the acids ina one-gram sample of the naphthenic acids. An especially advantageoussource of naphthenates having desirable properties for use in theinvention is the n'aphthen'ates produced in the refining of petroleumand its various products, particularly lubricating oil. Methods whichare suitable for producing naphthenates which-may be used in the newcompositions of the invention, provided suitable starting materials areselected and/or the :naphthenic acids are properly treated to insurethat the final product will be naphthenates hjaving acid numbers lessthan 200, preferably acid numbers ofabout to 175, include, forexamplefa'lkali treatment of acid-refined petroleum distillates, or thecaustic distillation of mineral oils, particularly oils from Texas andCalifornia crudes, to obtain oil-containing naphthenates which may beused as such or maybe partially purified'by acidtreatment or morecompletely deoiled by dispersion in an aqueous medium followed byde-emulsification in the presence of a solventfor-the oil. The usualcommercialnaphthenates do not satisfythisrequirement, but are mixturesfrom which 'naphthe'nic acids of suitable-acid numbers maybe separatedfor use according to the invention; "Thus, naphthenic acids having therequired acid number 'may b'e separated from their mixtures withundesired naphthenic acids of higher acid number by fractionallydistilling off the latter andlusing' only he a ihen a rboil n ab e a ou200 C- ivrfilmm-ifiep es ereart cu a .suitabl a n t n [a s bo in bet e au 250 ,Q-andfififl" a z dmm-"fi re sa Petrol um qi wh p boi ab efiqw a0-5 mm- H pre sure, esnecial yirai n i luhr cati c il o 'the introducingthe precipitant.

like boiling between about 250 C. and 350 C. at 0.5 mm. Hg pressure, arepreferred sources of the naphthenates used in the new compositions.

The chosen naphthenate or naphthenate mixture corresponding tonaphthenic acids having acid numbers less than 200 is preferably used insizing as an aqueous emulsion with a sizing agent, preferably a sizingagent of the hydrocarbon type, most preferably the aromatic extracts ofmineral oils previously referred to. It is a special advantage of thesenaphthenates that they not only improve the sizing but also are capableof forming stable emulsions of the water-in-oil type with hydrocarbontype sizing agents, particularly the cyclic extracts of petroleum whichmay be readily inverted to emulsions of the oil-in-water'type which arequite stable, yet are precipitable in the presence of paper fibers bythe usual paper makers precipitants. This unusual combination ofdesirable properties makes it feasible. to prepare very cheaply highlyeffective sizing compositions as concentrated water-in-oil typeemulsionswhich can be conveniently shipped"'a't' low cost,

stored until needed, and readily diluted at the paper mill withoutdifficulties from phase separation or loss in sizing power to formemulsions of the oil-in-water type which can be used for sizing althoughas a rule it is more advantageously introduced when the beating has beensubstantially completed. The sizing may also be carried out in theJordan machine or at the screens. A

aecaao 4 solvents may be used for the preparation of such extracts,liquid sulfur dioxide, phenol, cresylic acid, furfural,beta,beta-dichlorethyl ether, nitrobenzene, the sulfolanes andsulfolenes, and the like being typical examples of suitable solvents.There are advantages in reextracting the initial extract with animmiscible solvent to improve the selectivity of the extraction. Thus,extraction of Edeleanu extracts of lubricating oils with gasoline or thelike has been found to improve the sizing properties of the compositionsproduced therefrom in accordance withthe invention. Other extractionmethods may be used."

Extracts of heavier petroleum oils such as the lubricating oils andresidual stocks are especially useful inthe new sizing compositions ofthe invention, but other fractions of petroleum or related hydrocarbonproducts can also be used successfully as sources of the extracts. Theex tracts may be derived, for example, from lubricant distillates-or.bright oils or cylinder stocks which may, for instance, range ingravity from I to 8 API at 60 F. They may be obtained wide range ofprecipitants may be used for fixing the new sizing compositions on thefibers. Alum, aluminum sulfate, calcium chloride, acids such as sulfuricor hydrochloric acid, and the like are all suitable, but paper makersalum is preferred. The precipitant may be added to the fiber along withthe size but generally it is preferred to add it later in the process,thus providing adequate time for uniform distribution of the size beforeThe amount of naphthenate sizewhich it will be most advantageous toemploy will dependvon the nature of the fibrous material being treated,the purpose for which it is intended, thetype of naphthenate chosen, andthe method of its application. As little as 0.2% based on the dry weightof the paper iseifective but up to 10% or more may be used, thepreferred range being usually about 0.5% to about 3%. V

In preparing emulsions of naphthenates of acid numbers less than 200'foruse according to the invention, a wide variety of materials may be usedas the dispersed phase. Oils or waxes such as, for example, mineralwaxes such as paraffin,

ceresin and montan wax, are useful when used either in combination orseparately. Hydrocarbons such as lubricating oils, spindle oil,asphalts, bitumens, etc. may thus be used.- However, there are specialadvantages in using cyclic extracts in preparing emulsions because thesenot only are highly desirable paper sizing compositions, as

previously pointed out, but also have other advantageous uses.

The cyclic extracts used in the new compositions of the invention arethe products of predominantly aromatic and naphthenic nature, obtainableby extracting petroleum or related oils, including hydrogenationproducts of coal-and the like, with solvents which are selective fornonparaffinic constituents. A wide variety of polar from" any mixed typepetroleum oil such as Mid- Continent or Coastal or California crude or,in lower yields, from Pennsylvania type oils. For use in sizing inaccordance with the invention, extracts boiling above 300 C. at 760 mm.Hg pressure are preferred, and most preferably extracts boiling fromabout 125 C. to 300 Cat 1 mm. Hg pressure are used. The more viscousextracts usually give emulsions with the most desirable sizingproperties but may be somewhat more difficult to emulsify. For thisreason extracts within the viscosity range of about -325 at 210 F., S.U. 8., have advantages, although more viscous extracts, e, g. 400 to5000 viscosity S. U. S. at 2l0 F., are preferred where it is notdisadvantageous to use a colloid mill or other such equipment orprolonged stirring or other methods of promoting emulsification in thepreparation of the initial emulsions and/or in their inversion toemulsions of the oil-in-water type. Extracts obtained from narrowfractions may be advantageously ,employed. It is often advantageous tofractionate the initial extract to separate fractions of especiallyadvantageous properties, thus, for instance. ithas been found that thehigher boiling 50% .to 7.5% of an Edeleanu extract'of lubricating .oilgives superior sizing judged by permeability to water of sized paper.Theproportion of naphthenate of acid number less than 200 to hydrocarbonused in preparing emulsions of these materials for paper sizing can bevaried but as a rule will be such as corresponds to about 3'to about'75, more preferably 5 to 50, per cent by Weight of naphthenate based onthe total weight of naphthenate and hydrocarbon. Where desirable, theemulsifying properties of the naphthenate chosen may be supplemented byaddition of a small amount, usually about'0.l% to 5% by weight of thenaphthenate and hydro.- carbon present, of another emulsifying agent.Soap, higher alkyl sulfate salts, organic sulfonic acid salts,particularly alkyl aryl sulfonates,-sodium rosinate and the like may beusedi-as supplementary emulsifying agents where the naphthenate employedis not itself sufiicient to insure the desired stability in theemulsion, either on account of the acid number of the naphthenic acidused being too high or because an insuflicient amount is used. Themostadvantageous sizing emulsions, however, are those made fromnaphthenates of acid. number less than 200 without other emulsifyingagents.

In order to obtain emulsions of the most desirable particle size forpaper sizing, it has been found advantageous to mix together the chosenn'aphthenic acid or naphthenic acid mixture and hydrocarbon, preferablythe previously described cyclic extract, with warming necessary toinsure uniform distribution of viscous hydrocarbons. and then to addsufficient aqueous base to substantially neutralize the naphthenic acidspresent. In this way a moderately fine, 'quite uniform emulsion of thewate-in-oil type may be prepared which on further dilution can beconverted to an oil-in-water type emulsion of very fine particle sizehighly advantageous in paper sizing. The transition point for the changein the type of the emulsion is generally about 40% to about50% water inthe emulsion.

A wide variety of different alkaline agents may be used in preparing theemulsions. Hydroxides or carbonates of alkali metals or ammonia aresuitable; sodium or potassium hydroxides are preferred hydroxides,however, becauseof their relatively low cost. The corresponding,particularly the sodium and potassium, carbonates require highertemperatures and are thus somewhat less preferable. Alkaline earthhydroxides such, for example, as calcium and magnesium hydroxides, etc.may also be used. For certain purposes, neutralization with an organicbase such, for example, as aliphatic, alicyclic or aromatic, primary,secondary or tertiary amines or quaternary a1.-- monium bases, isadvantageous. Water soluble amines such, for instance, asdimethylamine,-prcpylamine, cyclohexlamine, the ethanolamines, etc. maybe used in such cases. The chosen base is preferably employed as anaqueous solution of about 5% to about 30% concentration, most preferablyabout 5% to concentration. The moststable emulsionsare prepared by theuse of slightly less than the stoichiometric amount of base, preferablyabout 85% to 95% of the amount required for neutralization of thenaphthenic acids. A pH of about 8 to 13, preferably 10 to 11.5, isadvantageous in the final emulsion. If the initial emulsion is too acidor alkaline it can be brought to the desired pH by adding a weak base oracid.

'As previously indicated the emulsionsizes of the invention made withnaphthenates of acid number less than 200 are highly stable compositionswhich do not coagulate readily in the absence of cellulose fibers.However, these emulsions occasionally show some phase separation on longstanding but can be brought backto a homogeneous state by shaking orstirring. Even this separation can be eliminated by adding small amountsof protective colloids such, for instance, as casein and gums.

The invention is, of course, not limited to the method of preparing newemulsion sizes de scribed, asotherprocedures arealso applicable. Thus,for example, it is feasible to produce highly effective sizes by mixingtogether a cyclic extract of lubricating oil, for instance, andpreviously neutralized naphthenic acids of acid number less than 200,preferably .the sodium naphthenates, followed by dilution with therequired amount of water. The emulsions of sodium naphthenates of :-acidnumber less than 200'and high boiling hydrocarbons obtainedv as bottomsfromzthe refining of petroleum :oils by distillation in the presence ofcaustic soda are also very suitable for sizing according to theinvention.

'In contrast with sizes usually used in the manufacture of paperand-cardboard :which are generally used in the form of very diluteseminsions, e. .g. of about 0.1% to 0.5% concentration, the products ofthe invention can often :be used in much more concentrated form. Thus,in the manufacture of paper and cardboard they may be employed as 20% to50% emulsions o-f theoilin-water type quite successfully.

The new sizes of the invention, as previously pointed out, may be usedwithout any other change in the paper-making process. "They arepreferably precipitated on the fiber with paper makers alum and a pH ofabout 4.5 too, depending on the type of pulp, is desirable duringprecipitation. If necessary, the pI-I may be controlled by addingdiluteacid in the beater. About 25 grams of aluminum sulfate perkilogram of dry stuff in the beater gives satisfactory precipitation.Too much aluminum in the paper should be avoided as it adversely affectsthe permeability to water.

The sizes of the invention may be used in making papers filled withkaolin and the like as well as in making unfilled papers. The new sizesalso do not give any complications with paper dyestuffs. They are notonly cheaper than the usual sizes but also have the advantage that thesizing effect obtained is greater than would be expected from sizingwith either of the constituent parts of the product alone.

The following examples illustrate typical applications of the sizes ofthe invention and show their advantages in sizing paper.

Example I To show the superiority of the compositions of the inventionto rosin in emulsion sizes using a furfural extract of a lubricatingoildistillate of California petroleum (motor grade lubricating oil having aviscosity of 200 at 210 F'.,.S. U..S:), four emulsions wereprepared-byadding suflicient 10% sodium hydroxide solution to mixtures.of the extract and de-oilednaphthenic acid of :acid number 150or'rosinto-saponify of the acid. The resulting water-in-oil emulsion wasmixed with moderate agitation for 15 minutes. The emulsion was theninverted by addition of water to form a 50 oil-in-Water emulsion.Agitation during inversion was afforded by an Eppenbach homo-mixer usingas high a rate of shear as possible without incorporation of air.

The size emulsions were diluted to 1% oil-inwater and addedto kraftbeaten pulp (2 of size' P t b 'Purgstoty or s y weig weight of naph-Parts by am (if exttheiiicf weight g rac aci o of rosin used l50'acid(mm') (mm'2) number Using a lower boiling fraction" of furfural extractof viscosity 60 at 210 F. instead of that used above, the sizing was notas satisfactory but was still superior in the case of the sizecontaining naphthenate of acid number 150. 5

Similar good results are obtained when sulfite pulp is substituted forthe kraft pulp.

Example II The fluorescent size test was carried out as dedescribed byVan den Akker et al. in the Paper Trade Journal, vol. 109, page 33(1939), and shows clearly the superiority of the naphthenatearomaticextract mixture.

Example IV The superior stability of the emulsion compo-' sitions of theinvention is shown by the following results for emulsions of a highlyaromatic extract having a viscosity at 210 F. of 2030 obtained from anindustrial lubricating oil distillate of California petroleum having aviscosity of 200 at 210 F., S. U. S. All the emulsions were prepared inthe same way.

. Size test, sec. Dilution Water TAPPI pH of standard Sizing agentAgitator emul- T 51011 1 5' 3 '7 1 ,0 a Type 0. size size Rosin 31 32Hydrocarbon-naphthenate mixture. Propeller 31 39 Do do 33 43 Homomixer.33 41 32 40 34 40 34 38 1 pH adjusted with boric acid.

These results show that under a wide range of conditions the newcompositions of the invention are fully equal or slightly superior tothe standard rosin size at lower size concentrations and 40 are markedlysuperior thereto at higher concentrations. Electron micrographs of thesized papers showed that the particles of size on the fibers were muchsmaller and more uniformly distributed in the case of the mixture oflubrieating oil residue and naphthenates of acid number 150 than withthe rosin size.

Example III Comparative tests were made on the use of an aromaticextract of petroleum having a viscosity at 210 F. of 537 'S. U. S. withnaphthenic acids of 150 acid number containing about 3% of oil, on theone hand, and an equal amount 55 of rosin, on the other. The emulsionswere prepared by mixing 80 parts of the extract with parts of thenaphthenic acid or rosin, 1.9 to 2.1 parts of sodium hydroxide and 100parts of water in a Waring Blendor for minutes at 0., then adding waterto form a 50% emulsion and continuing the mixing for 30 minutes. Theemulsions were used to size kraft paper, as described in Example I, withthe following re- Composition (parts by weight per parts Stabilit water)y Emulsion particle size 95 lub. oil distillate, 5

parts sodium naphthenate (acid number Stable Majority about 0.2

microns.

Emulsion broke Large, several greater over night.

than 20 microns.

Emulsion broke Could not be measured immediately.

because of emulsion instability.

Sizing tests with the above lubricating oil distillate-sodiumnaphthenate emulsion, using 1.95% size based on the dry weight of kraftpulp, gave the following results:

Dry indicator test (TAP- PI standard proc dure) 41 sees. for penetrationFluorescent size test seconds The other emulsions were too unstable towarrant size testing.

7 Example V The superiority of the emulsions of aromatic extracts withnaphthenates of acid numbers less than 200 compared with similarcomposition prepared with'high acid number naphthenates is shown by thefollowing results for emulsions containing 50% water, 45.5% of anEdeleanu extract of viscosity 79.8 S. U. S. at 210 F. from a lubricatingoil distillate of viscosity 60 S. U. S.

Acid Aver: Ml. of upper phase number age separated from of oilmole- Per-80 m1, of emulfree cular cent 5 i o n a f t e r Form ofnaphthenate naphweight oil in (hours) thenic of crude acid, ifiiphacid mg. emc KOH/gacid 4 8 20-24 44-48 196 Sodium naphthenate. 118 475 3. 2 2 2.

W ile the advanta e of t e ne omp itio 'of the invention in sizing paperand related fibrous materials, particularly cellulose fibers and thelike, have been emphasized in the foregoing because of the specialimportance of this novel application of these products, they have manyother advantageous uses. Thus, for example, they are particularlysuitable as agricultural sprays where a thin, sticky residual film onthe plants is desirable to keep the insecticide or fungicide or the likefrom being blown off after application. They are also useful in aqueouspaint emulsions, particularly when, as is preferred, extracts havingdrying properties are used in their preparation. Such emulsions areadvantageously pigmented by adding a separately prepared slurry ofpigment, for example, lithopone, zinc oxide, titanium dioxide, ochre,iron oxide or the like, preferably containing glue, to the emulsion withstirring, in the proportions of about 50 to 700 parts of pigment per 100parts of emulsified extract and naphthenate.

It will thus be seen that the new compositions of the invention offermany advantages not only as sizing compositions but also in a variety ofother uses. It will therefore be understood that the invention is notlimited to the applications given as illustrations nor to the details ofoperation disclosed by way of example.

I claim as my invention:

1. Paper pulp having on the surface thereof a precipitate from anemulsion of a sizing agent comprising cyclic components of a lubricatingoil fraction of petroleum soluble in a polar solvent having apreferential solubility for the aromatic and naphthenic components, andhaving a viscosity of 75 to 5000 S. U. S. at 210 F., together withsodium naphthenate salts derived from naphthenic'acids having an averageacid number between 100 and 200, the amount of said naphthenic saltsbeing from about 3% to 75% of the total weight of said salts and saidcyclic components.

2. A process of preparing an emulsion of hydrocarbon with water whichcomprises intimately contacting a liquid cyclic extract of predominantlyaromatic and naphthenic nature derived from a mineral oil with 5% to 50%by weight of naphthenic acids having an average acid number betweenabout 100 and 200, reacting the mixture with an aqueous solution ofsodium hydroxide of 5% to 15% concentration sufiicient to neutralize 85%to 95% of the naphthenic acid a d. form an muls on o the water n-o t pand diluting said emulsion with'water to bring the total water contentof the mixture to 40% to and form an emulsion of said hydrocarboil inwater.

3. An emulsion of the water-in-oil type suitable for use as a siz ngagent and for other purposes comprising to parts of a mixture of cycliccomponents of a lubricating oil fraction of petroleum soluble in a polarsolvent having a preferential solubility for the aromatic and naphtheniccomponents, together with a naph thenate salt derived from naphthenicacids having an average acid number between about and 200 in an amountfrom about 3% to 75% based on the total weight of said cyclic componentsand said naphthenate salt, and 20 to 40 parts of water.

4. A mixture of a cyclic extract of predominantly aromatic andnaphthenic nature obtained by extracting a lubricating oil fraction ofpetroleum with a polar solvent having a preferential solubility for thearomatic and naphthenic components, together with 3% to 50% of anaphthenate salt derived from naphthenic acids having an average acidnumber between 100 and 200, said percentage being based on the totalweight of said nap-hthenate salt and extract present.

5. Cellulose fibers having the surfaces thereof coated with aprecipitate of a cyclic extract of predominantly aromatic and naphthenicnature from a mineral oil, together with from about 3 to 75% ofnaphthenate salts derived from naphthenic acids having an average acidnumber of between 100 and 200, said percentage being based on the totalweight of naphthenates and extract present.

6. A paper product comprising cellulose fibers having distributed ontheir surface 0.5% to 5% by weight of the dry fibers of a mixture of asizing agent made up of a cyclic extract of a mineral oil, which extractis of predominantly aromatic and naphthenic nature, together with anaphthenate salt derived from naphthenic acids having an average acidnumber between about 100 and 200, said naphthenate salt being present inthe amount of 3% to 50% of the total weight of said sizing agent andnaphthenate salt.

7. Cellulose fibers having on their surface a sizing agent precipitatedthereon from an emulsion of the oil-in-water type essentially comprisingat least 40% by weight of Water, a liquid cyclic extract ofpredominantly aromatic and naphthenic nature derived from petroleumhydrocarbons and having a viscosity of 75 to 5000 S. U. S. at 210 F.,together with sodium naphthenate salts derived from naphthenic acidshaving an average acid number of between about 100 and 200, said sodiumnaphthenates being present in an amount of 3% to 50% by weight of thetotal amount of said naphthenate salts and extract.

8. Paper pulp having on the surface thereof a mixture of cycliccomponents soluble in solvents having a preferential solubility for thearcmatic and naphthenic components extracted, to-

.gether with naphthenate salts derived from total weight of naphthenatesalts and said cyclic components,

9. An emulsion of the oil-in-water type essentially comprising at least40% by Weight of water, a liquid mixture of cyclic components ofpetroleum having a viscosity of 75 to 5000 S. U. S. at 210 F. which aresoluble in a polar solvent having a preferential solubility for thearomatic and naphthenic components, and sodium naphthenate salts derivedfrom naphthenic acids having an average acid number between about 100and 200, said sodium naphthenates being present in an amount of 3% to50% by Weight of the total amount of naphthenates and said cycliccomponents.

10. An emulsifiable composition comprising a mixture of cycliccomponents extracted from petroleum hydrocarbon having a. viscosity ofat least 100 S. U. S. at 210 F., and which are soluble in solventshaving a preferential solubility for aromatic and naphthenic components,together with sodium naphthenate salts derived from naphthenic acidshaving an average acid number between 100 and 175.

THEODORE F. BRADLEY.

References Cited in the file of this patent UNITED STATES PATENTS NumberNumber Name Date Frizell Apr. 27, 1926 Becher July 31, 1928 Novak May 8,1934 Gay Apr. 7, 1936 Rich et al Sept. 10, 1940 Bradley July 14, 1942Zimmer et a1. Jan. 25, 1944 Gaver May 2, 1944 Butcher Apr. 30, 1946Gregg July 1, 1947 Roon July 8, 1947 Kaberg et al Aug. 17, 1948 FOREIGNPATENTS Country Date Switzerland July 1, 1921 Germany Nov. 27, 1922OTHER REFERENCES Gershzon, Chemical Abstracts, vol. 33, p. 8989.Gershzon, Chemical Abstracts, v01. 34, p. 3119.

5. CELLULOSE FIBERS HAVING THE SURFACES THEREOF COATED WITH APRECIPITATE OF A CYCLIC EXTRACT OF PREDOMINANTLY AROMATIC AND NAPHTHENICNATURE FROM A MINERAL OIL, TOGETHER WITH FROM ABOUT 3 TO 75% OFNAPHTHENATE SALTS DERIVED FROM NAPHTHENIC ACIDS HAVING AN AVERAGE ACIDNUMBER OF BETWEEN 100 AND 200, SAID PERCENTAGE BEING BASED ON THE TOTALWEIGHT OF NAPHTHENATES AND EXTRACT PRESENT.